如何为DBIx::Class ORM强制连接类型？

Question

我有代码：

$self->search_related( 'Servers', {
    'Servers.active' => 'yes',
    'Ips.state'      => 0,
},{
    join => { Subnets => 'Ips' }
})->as_query;

这会产生：

SELECT "me"."id", "me"."active", "me"."ip_id", "me"."locality_id", "me"."hostname", "me"."ca_certificate", "me"."openvpn_static_key", "me"."l2tp_key", "me"."description", "me"."notes" 
FROM "servers" "me" 
LEFT JOIN "subnets" "Subnets" ON "Subnets"."server_id" = "me"."id" 
LEFT JOIN "ips" "Ips" ON "Ips"."subnet_id" = "Subnets"."id" 
WHERE ( ( "Ips"."state" = ? AND "Servers"."active" = ? AND "me"."locality_id" = ? ) )

我可以通过以下方式重写此代码：

$self->search_related( 'Servers', { active => 'yes' } )
  ->search_related( 'Subnets' )
  ->search_related( 'Ips', { state => 0 } )
  ->as_query

这将产生以下结果：

SELECT "Ips"."id", "Ips"."subnet_id", "Ips"."ip", "Ips"."package_id", "Ips"."state", "Ips"."notes" 
FROM "servers" "me"  
JOIN "subnets" "Subnets" ON "Subnets"."server_id" = "me"."id"  
JOIN "ips" "Ips" ON "Ips"."subnet_id" = "Subnets"."id" 
WHERE ( ( "active" = ? AND "me"."locality_id" = ? AND "state" = ? ) )

但是有没有办法用first case force JOIN代替LEFT JOIN呢？

Answer 1

联接类型由DBIC架构中的关系定义。当你需要一个不同的连接类型进行搜索时，建议只定义另一个连接类型的关系，例如has_many('Subnets_full_join', ...)，并在搜索中使用它，而不是常规的连接类型。